1. Technical Field
The present invention relates to a receiver circuit, and in particular, to a receiver circuit that amplifies input data.
2. Related Art
Generally, a receiver circuit in a semiconductor integrated circuit is used to amplify data by increasing the voltage swing when input data is transmitted to an output terminal.
Such a receiver circuit includes a sense amplifier 100 and a latch unit 200, as shown in FIG. 1.
The sense amplifier 100 receives an up input signal IN and a down input signal INb and outputs an up output signal OUT and a down output signal OUTb in response to a clock signal CLK. Such a sense amplifier 100 includes an input unit to which the up input signal IN and the down input signal INb are input, an amplifying unit that amplifies the up input signal IN and the down input signal INb input through the input unit, and a driving unit that drives the amplifying unit. Each of the input unit, the amplifying unit, and the driving unit may include a plurality of NMOS transistors and a plurality of PMOS transistors.
The latch unit 200 latches the up output signal OUT and the down output signal OUTb output from the sense amplifier 200 so as to be fully swung, thereby generating output data RXDATA.
At that time, the sense amplifier, specifically, the input unit of the sense amplifier to which signals having opposite phases are input may include a pair of transistors having the same size.
However, even though the pair of transistors that configures the input unit is designed to have the same size, the component sizes of the transistor (for example, channel length, or channel width) may be varied during the manufacturing process, which generates an offset voltage.
Further, the sense amplifier is designed to perform amplification operating when voltages having opposite phases are input to the input unit thereof. In this case, unexpected noise may be input to any one of the transistors of the input unit, which causes malfunction of the transistor.
The offset voltage and noise may cause malfunction of the input unit of the sense amplifier such that an electric potential at the connection node of the input unit and the amplifying unit is changed, which results in the malfunction of the entire sense amplifier.